Effect of CeO_2 and Nanoscale WC on Wear Resistance of Laser Cladding WC Composite Coatings

摘要

Composite coatings with hard particle WC and nickel-base alloy matrix (Ni60B) were designed and made by laser cladding technology. The optimum content ratio between WC and nickel-base alloy as well as laser-cladding processing parameters was proposed by laser cladding tests. Small content of CeO_2 and nanoscale WC particles were added into the coatings in order to improve their performance. The phases and microstructures of the coatings were analysed by x-ray diffractometer and SEM. The dry sliding wear tests of the coatings were also conducted on an MM200 model tester. The effect of CeO_2 and nanoscale WC particles on wear resistance of the coatings was investigated. The result shows that the additions of CeO_2 or nanoscale WC particles can enhance the hardness and wear resistance of coatings because of the refinement of microstructures.